A rapid, fixed-point gas sampling device for deep boreholes in coal mines

Abstract

This invention belongs to the field of coal mine sampling technology, specifically a rapid fixed-point sampling device for methane in deep coal mine boreholes. It includes a drill rod, the output end of which is connected to a drill bit. A sampling tube is rotatably mounted around the drill rod, comprising a sampling channel and a compressed air channel. The top of the sampling tube at the compressed air channel is connected to the drill bit and sealed by a first sealing element, while the top of the sampling tube at the sampling channel is sealed by a second sealing element. An induced draft fan is connected to the outside of the sampling channel, and a sample collector is installed on the induced draft fan. A compressed air fan is also connected to the outside of the compressed air channel. This invention utilizes the principle of compressed air reverse circulation for rapid sampling. The compressed air fan delivers gas to the bottom of the borehole through the compressed air channel and the drill bit hole. The feed channel on the drill bit rotates and, under the action of air pressure, transports the coal cuttings from the drill bit to the sampling hole. The induced draft fan then draws the coal sample into the sample collector. Under the combined action of the compressed air fan and the induced draft fan, the pressure inside the borehole is balanced, thereby achieving rapid sampling.

Description

Technical Field

[0001] This invention belongs to the field of coal mine sampling technology, specifically a rapid sampling device for fixed-point gas sampling in deep coal mine holes. Background Technology

[0002] The determination of gas content requires fixed-point sampling. Domestic and foreign researchers have conducted extensive and in-depth research on fixed-point sampling. At present, the main sampling method is negative pressure injection coal sampling. However, negative pressure injection puts the coal sample in a negative pressure state, which affects the desorption rate of the coal sample and disrupts the desorption law of the coal sample. Moreover, the sampling success rate is low due to the influence of the negative pressure. Furthermore, negative pressure injection coal sampling generally uses a negative pressure sampler and a vacuum pump for gas extraction. Since the gas extraction volume of the negative pressure sampler is small and the location of the extracted gas is uncertain, the vacuum pump also has the problem of insufficient gas extraction volume. Therefore, the extracted gas sample may not be able to reflect the true situation of the gas in the goaf, which is not conducive to the monitoring of spontaneous combustion index gas in the goaf.

[0003] Therefore, it is necessary to provide a rapid sampling device for gas at fixed points in deep mine holes to solve the problems mentioned in the background art. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides the following technical solution: a rapid, fixed-point gas sampling device for deep boreholes in coal mines, comprising a drill rod, the output end of which is connected to a drill bit, and a sampling tube rotatably mounted around the drill rod. The sampling tube includes a sampling channel and a compressed air channel. The top end of the sampling tube at the compressed air channel is connected to the drill bit and sealed by a first sealing element, while the top end of the sampling tube at the sampling channel is sealed by a second sealing element. An induced draft fan is connected to the outside of the sampling channel, and a sample collector is connected to the induced draft fan. A compressed air fan is also connected to the outside of the compressed air channel.

[0005] The compressed air channel is fitted on the outside of the drill pipe, and the sampling channel is fitted on the outside of the compressed air channel.

[0006] The first sealing component includes a sealing shell I and a sealing disc I. The bottom of the sealing shell I is fixedly connected to the top of the sampling tube at the compressed air channel. The sealing shell I has a plurality of perforations evenly arranged on it, and a liquid injection tube is provided on the perforations for sealing connection. The sealing shell I has a sealing disc I rotatably connected inside it. The sealing disc I has a plurality of water injection holes and compressed air holes evenly arranged on it, with the same diameter as the perforations. The water injection holes and compressed air holes are arranged alternately, and there is a perforation difference between the water injection holes and the compressed air holes.

[0007] The upper part of the sealing shell I is provided with an arc-shaped sealing cavity, and the sealing plate I is provided with a sliding plate corresponding to the position of the arc-shaped sealing cavity. The sliding plate can slide inside the arc-shaped sealing cavity, and spring I is provided in the sliding plate and the arc-shaped sealing cavity.

[0008] The second sealing component includes a sealing shell II and a sealing disc II. The bottom of the sealing shell II is fixedly connected to the top of the sampling tube at the sampling channel position. The sealing shell II has multiple sampling holes. The sealing disc II is rotatably connected inside the sealing shell II. The sealing disc II has through holes with the same diameter and number as the sampling holes. The through holes are alternately connected to and sealed with the sampling holes.

[0009] The sealing disc II is provided with a push plate, and the sealing shell II is provided with a pressure chamber. The pressure chamber is connected to the sampling channel. A pressure block is slidably connected to the pressure chamber. A spring II is provided between the pressure block and the pressure chamber. A pull rod is hinged between the pressure block and the push plate.

[0010] The drill bit is conical, and a material conveying channel is provided on the inclined surface of the drill bit.

[0011] A transition cavity is provided at the top of the sealing shell I where it connects to the drill bit.

[0012] The drill bit is provided with multiple drill holes, and the drill holes are connected to the transition cavity.

[0013] The outer surface of the sampling tube is provided with multiple slides, and a sealing mechanism for sealing boreholes is slidably disposed on the slides.

[0014] The sealing mechanism includes a sealing seat, a sealing gasket, and an airbag. The sealing seat is slidably disposed in a slide rail, and a sealing gasket is fixedly disposed on the sealing seat. An airbag is disposed in the sealing gasket.

[0015] Compared with the prior art, the present invention provides a rapid and pinpoint sampling device for methane in deep coal mine boreholes, which has the following advantages:

[0016] In this invention, rapid sampling is achieved using the principle of compressed air reverse circulation. A compressed air compressor delivers gas to the bottom of the borehole through a compressed air channel and a drill bit hole. A feed channel is inclined on the drill bit, which, through rotation and under the action of air pressure, transports the coal cuttings from the drill bit to the sampling hole. An induced draft fan then draws the coal sample into a sample collector. The combined action of the compressed air compressor and the induced draft fan balances the pressure inside the borehole, thus enabling rapid sampling. Furthermore, a liquid injection pipe, a first sealing element, and a second sealing element are installed on the sampling tube to cool the drill bit during drilling. The first and second sealing elements seal the sampling tube before and after sampling, preventing coolant and other impurities from entering the sampling tube and contaminating the coal sample, thereby improving sample purity and making the test results more accurate. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0018] Figure 2 This is a schematic diagram showing the connection between the sampling tube and the first sealing element, the second sealing element, and the sealing structure in this invention;

[0019] Figure 3 This is a schematic diagram of the structure of the first sealing component in this invention;

[0020] Figure 4 This is a schematic diagram of the structure of the second sealing component in this invention;

[0021] Figure 5 This is a schematic diagram of the sealing mechanism in this invention;

[0022] In the diagram: 1. Drill rod; 2. Drill bit; 21. Material conveying channel; 22. Drill bit hole; 3. Sampling tube; 31. Sampling channel; 32. Compressed air channel; 33. Liquid injection pipe; 34. Slide rail; 35. Sealing mechanism; 351. Sealing seat; 352. Sealing gasket; 353. Airbag; 4. First sealing component; 41. Sealing shell I; 411. Perforation; 412. Arc-shaped sealing cavity; 413. Spring I; 414. Transition cavity; 42. Sealing plate I; 421. Water injection hole; 422. Compressed air hole; 423. Slide plate; 5. Second sealing component; 51. Sealing shell II; 511. Sampling hole; 512. Air pressure cavity; 513. Air pressure block; 514. Pull rod; 515. Spring II; 52. Sealing plate II; 521. Through hole; 522. Push plate. Detailed Implementation

[0023] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the present invention.

[0024] like Figure 1-5 As shown, a rapid sampling device for fixed-point methane in deep coal mine boreholes includes a drill rod 1, the output end of which is connected to a drill bit 2. A sampling tube 3 is rotatably mounted on the periphery of the drill rod 1. The sampling tube 3 includes a sampling channel 31 and a compressed air channel 32. The top end of the sampling tube 3 at the position of the compressed air channel 32 is connected to the drill bit 2 and sealed by a first sealing element 4. The top end of the sampling tube 3 at the position of the sampling channel 31 is sealed by a second sealing element 5. An induced draft fan is connected to the outside of the sampling channel 31, and a sample collector is connected to the induced draft fan. An air compressor is connected to the outside of the compressed air channel 32.

[0025] The compressed air channel 32 is fitted on the outside of the drill rod 1, and the sampling channel 31 is fitted on the outside of the compressed air channel 32.

[0026] The sample collector is also equipped with a tilted mesh, which can separate the sample from the air to achieve the purpose of sample collection.

[0027] During implementation, drill rod 1 and drill bit 2 are used to drill a hole. During the drilling process, coolant is supplied to drill bit 2 through injection pipe 33 to cool it. When drill bit 2 reaches the designated position, the supply of coolant to drill bit 2 is stopped. Then, the hole is sealed by sealing mechanism 35, and the air compressor and induced draft fan are turned on. Drill bit 2 is used to cut coal dust, and the coal dust is transported to sampling hole 511 through feed channel 21 of drill bit 2. Then, the coal dust sample is sucked into the sample collector by induced draft fan. Under the action of gas blown by air compressor, the pressure inside the hole is balanced, and rapid sampling is achieved.

[0028] The first sealing component 4 includes a sealing shell I 41 and a sealing disc I 42. The bottom of the sealing shell I 41 is fixedly connected to the top of the sampling tube 3 at the position of the compressed air channel 32. The sealing shell I 41 is uniformly provided with a plurality of perforations 411. A liquid injection tube 33 is provided on the perforations 411 and sealed. The sealing shell I 41 is provided with a rotatably connected sealing disc I 42. The sealing disc I 42 is uniformly provided with a plurality of water injection holes 421 and compressed air holes 422 with the same diameter as the perforations 411. The water injection holes 421 and the compressed air holes 422 are alternately arranged, and there is a perforation 411 between the water injection holes 421 and the compressed air holes 422.

[0029] The air pressure hole 422 and the water injection hole 421 are provided with a perforation difference, so that when the water injection hole 421 is connected to the perforation 411, the air pressure hole 422 is in a blocked state. When the water injection hole 421 is no longer injecting coolant and is in a blocked state, the air pressure hole 422 is in a connected state with the perforation 411, so that the water injection hole 421 and the air pressure hole 422 are always separated and will not be connected.

[0030] The upper part of the sealing shell I 41 is provided with an arc-shaped sealing cavity 412. The sealing plate I 42 is provided with a sliding plate 423 corresponding to the position of the arc-shaped sealing cavity 412. The sliding plate 423 can slide inside the arc-shaped sealing cavity 412. The sliding plate 423 and the arc-shaped sealing cavity 412 are provided with spring I 413.

[0031] In the initial state of implementation, the water injection hole 421 is in a closed state, and the compressed air hole 422 is in a connected state. Then, coolant is injected into the perforation 411 through the injection pipe 33. The sliding plate 423 slides along the sealing cavity 412 under hydraulic action and drives the sealing plate I 42 to rotate, so that the water injection hole 421 is connected to the perforation 411, and the compressed air hole 422 of the sealing plate I 42 is blocked, so that the coolant is injected into the transition cavity 414 and cools the drill bit 2 through the drill bit hole 22. When sampling, the injection of coolant is stopped, the sliding plate 423 is reset under the action of the spring I 413, and drives the sealing plate I 42 to rotate, so that it blocks the water injection hole 421 and connects the compressed air hole 422. Gas is input to the bottom of the drill bit 2 using the compressed air fan, and coal dust is drawn into the sample collector by the induced draft fan. Rapid sampling is carried out through the compressed air reverse circulation principle.

[0032] The second sealing component 5 includes a sealing shell II 51 and a sealing disc II 52. The bottom of the sealing shell II 51 is fixedly connected to the top of the sampling tube 3 at the sampling channel 31. The sealing shell II 51 has multiple sampling holes 511. The sealing disc II 52 is rotatably connected inside the sealing shell II 51. The sealing disc II 52 has through holes 521 with the same diameter and number as the sampling holes 511. The through holes 521 are alternately connected to and sealed with the sampling holes 511.

[0033] The sealing disc II 52 is provided with a push plate 522, and the sealing shell II 51 is provided with a pressure chamber 512. The pressure chamber 512 is connected to the sampling channel 31. The pressure chamber 512 is slidably connected to a pressure block 513. A spring II 515 is provided between the pressure block 513 and the pressure chamber 512. A pull rod 514 is hinged between the pressure block 513 and the push plate 522.

[0034] During implementation, the sampling hole 511 is in a blocked state. When sampling, an induced draft fan is used to draw air into the sampling channel 31. Since the sampling hole 511 is in a sealed state, the air pressure block 513 slides along the air pressure chamber 512 under the action of air pressure, and pulls the sealing disc II 52 to rotate through the pull rod 514, so that the sampling hole 511 is connected to the through hole 521, thereby extracting the coal sample. This ensures that the sampling tube 3 is in a sealed state before sampling, preventing the coolant or other debris from entering the sampling channel 31 during drilling and contaminating the sample, thus effectively improving the sample quality.

[0035] The drill bit 2 is conical, and a material conveying channel 21 is inclinedly provided on the surface of the drill bit 2.

[0036] The top of the sealing shell I 41 is provided with a transition cavity 414 at the connection between it and the drill bit 2.

[0037] The drill bit 2 is provided with a plurality of drill holes 22, and the drill holes 22 are connected to the transition cavity 414.

[0038] The material conveying channel 21 is inclined so that the coal dust can be rotatably conveyed to the sampling hole 511, and gas is delivered to the bottom of the borehole through the drill bit hole 22 by a compressor, thereby performing compressed air and rapid sampling.

[0039] The outer surface of the sampling tube 3 is provided with multiple slides 34, and a sealing mechanism 35 for drilling sealing is slidably disposed on the slides 34.

[0040] The sealing mechanism includes a sealing seat 354, a sealing gasket 352, and an airbag 353. The sealing seat 354 is slidably disposed in the slide rail 34, and the sealing gasket 352 is fixedly disposed on the sealing seat 354. The airbag 353 is disposed in the sealing gasket 352.

[0041] During implementation, the sealing mechanism 35 is used to seal the borehole, forming a closed space inside the borehole. This ensures that the air compressor and the induced draft fan form a reverse air circulation for rapid sampling. The slide 34 is also provided so that the sealing mechanism 35 can slide along the sampling tube 3 after sealing, effectively preventing the movement of the drill rod 1 and drill bit 2 during sampling from affecting the sealing mechanism 35.

[0042] In summary, this device utilizes the principle of compressed air reverse circulation for rapid sampling. A compressed air compressor delivers gas to the bottom of the borehole through the compressed air channel 32 and the drill bit hole 22. Under the action of the material conveying channel 22, the coal cuttings from the drill bit 2 are transported to the sampling hole 511. An induced draft fan then draws the coal sample into the sample collector. The combined action of the compressed air compressor and the induced draft fan balances the pressure inside the borehole, thus achieving rapid sampling. Before sampling, coolant can be injected into the drill bit 2 through the injection pipe 33 to cool it. The first sealing component 4 and the second sealing component 5 seal the sampling tube 3 before and after sampling to prevent coolant and other impurities from entering the sampling tube 3 and contaminating the coal sample, further improving sample purity and making the test results more accurate.

[0043] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A rapid, pinpoint gas sampling device for deep boreholes in coal mines, characterized in that, The system includes a drill rod (1), the output end of which is connected to a drill bit (2). A sampling tube (3) is rotatably fitted around the drill rod (1). The sampling tube (3) includes a sampling channel (31) and a compressed air channel (32). The top end of the sampling tube (3) at the position of the compressed air channel (32) is connected to the drill bit (2) and sealed by a first sealing element (4). The top end of the sampling tube (3) at the position of the sampling channel (31) is sealed by a second sealing element (5). An induced draft fan is connected to the outside of the sampling channel (31). A sample collector is connected to the induced draft fan. An induced draft fan is connected to the outside of the compressed air channel (32). The first sealing component (4) includes a sealing shell I (41) and a sealing disc I (42). The bottom of the sealing shell I (41) is fixedly connected to the top of the sampling tube (3) at the position of the compressed air channel (32). The sealing shell I (41) is uniformly provided with a plurality of perforations (411). The perforations (411) are provided with a sealed injection tube (33). The sealing shell I (41) is rotatably connected to the sealing disc I (42). The sealing disc I (42) is uniformly provided with a plurality of water injection holes (421) and compressed air holes (422) of the same size as the perforations (411). The water injection holes (421) and the compressed air holes (422) are alternately arranged. There is a perforation (411) between the water injection holes (421) and the compressed air holes (422). The upper part of the sealing shell I (41) is provided with an arc-shaped sealing cavity (412), and the sealing plate I (42) is provided with a sliding plate (423) corresponding to the position of the arc-shaped sealing cavity (412). The sliding plate (423) can slide in the arc-shaped sealing cavity (412), and the sliding plate (423) and the arc-shaped sealing cavity (412) are provided with spring I (413). The second sealing component (5) includes a sealing shell II (51) and a sealing disc II (52). The bottom of the sealing shell II (51) is fixedly connected to the top of the sampling tube (3) at the sampling channel (31). The sealing shell II (51) has multiple sampling holes (511). The sealing disc II (52) is rotatably connected inside the sealing shell II (51). The sealing disc II (52) has through holes (521) with the same diameter and number as the sampling holes (511). The through holes (521) and the sampling holes (511) are alternately connected and sealed. The sealing plate II (52) is provided with a push plate (522), and the sealing shell II (51) is provided with a pressure chamber (512). The pressure chamber (512) is connected to the sampling channel (31). The pressure chamber (512) is slidably connected with a pressure block (513). A spring II (515) is provided between the pressure block (513) and the pressure chamber (512). A pull rod (514) is hinged between the pressure block (513) and the push plate (522).

2. The rapid and pinpoint sampling device for deep-hole gas sampling in coal mines according to claim 1, characterized in that, The compressed air channel (32) is fitted on the outside of the drill rod (1), and the sampling channel (31) is fitted on the outside of the compressed air channel (32).

3. The rapid and pinpoint sampling device for deep-hole gas sampling in coal mines according to claim 1, characterized in that, The drill bit (2) is conical, and a material conveying channel (21) is provided on the inclined surface of the drill bit (2).

4. The rapid and pinpoint sampling device for deep-hole gas sampling in coal mines according to claim 1, characterized in that, The top of the sealing shell I (41) is provided with a transition cavity (414) at the connection between it and the drill bit (2). The drill bit (2) is provided with multiple drill holes (22), and the drill holes (22) are connected to the transition cavity (414).

5. A rapid, fixed-point gas sampling device for deep-hole coal mines according to claim 1, characterized in that, The outer surface of the sampling tube (3) is provided with multiple slides (34), and a sealing mechanism (35) for sealing the drill hole is slidably provided on the slides (34).

6. The rapid and pinpoint sampling device for deep-hole gas sampling in coal mines according to claim 5, characterized in that, The sealing mechanism (35) includes a sealing seat (351), a sealing gasket (352), and an airbag (353). The sealing seat (351) is slidably disposed in the slide (34), and the sealing gasket (352) is fixedly disposed on the sealing seat (351). The airbag (353) is disposed in the sealing gasket (352).

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